1. Field of the Invention
Embodiments of the present invention generally relate to a substrate support pin. More particularly, embodiments of the present invention relate to a support pin for large glass panels.
2. Description of the Related Art
Thin film transistors have been made on large glass substrates or plates for use in monitors, flat panel displays, solar cells, personal digital assistants (PDA), cell phones, and the like. These transistors are made by sequential deposition of various films including amorphous silicon, both doped and undoped silicon oxides, silicon nitride, and the like in vacuum chambers. The film deposition takes place in a single deposition chamber or system, or the substrate being processed is transferred among multiple deposition chambers. Within each deposition chamber, the substrate being processed typically rests on a support pedestal situated within the chamber. To facilitate transfer of the substrate between the deposition processes, support members, such as a plurality of pins for example, are mounted on an upper surface of the support member so that the substrate is spaced apart from the support pedestal. This allows a transfer mechanism such as a robot blade to slide underneath a back side of the substrate and lift the substrate off the support pedestal without causing damage to either the support pedestal or the substrate.
The support pins are most often vertical posts having a fixed height that are secured to an upper surface of the support pedestal. The support pins are usually rigid, providing no forgiveness for friction against the glass substrate disposed thereon. This friction most often results in unwanted particle contamination. Additionally, the support pins have a tendency to chip, bend, or break due to the repetitive loading and unloading of the substrates. These events occur due to misalignment of the substrate as the substrate enters and leaves the processing chamber. Damage to the pins may also occur due to operator error and most often, the damage is due to normal wear and tear. Accordingly, the support pins are usually replaced after extended periods of use, causing down time for removing the damaged pins and installing the replacements.
There is a need, therefore, for a support pin capable of reducing friction with a substrate disposed thereon, which increases the longevity of the support pin and reduces the amount of down time.